Train-control apparatus



A. J. BROOKINS.

- TRAIN CONTROL APPARATUS.

APPLICATION FILED JUNE 10. 1920.

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' TRAIN CONTROL APPARATUS.

APPLICATION FILED JUNE 10, 1920.

1,389,094. I PatentedAugao, 1921.

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A. J. BROOKINS.

TRAIN CONTROL APPARATUS.

APPLICATION FILED JUNE 10, 1920.

93 R 1T 0 m OW r E m A/ m m T A M UNITED STATES PATENT OFFICE.

ANDREW J. BBOOKINS, OF CHICAGO, ILLINOIS.

TRAIN-CONTROL APPARATUS.

Application filed June'lO, 1920. Serial No. 387,847.

' To all whom it may concern:

Be it known that 1, ANDREW J. BRooKINs, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Train-Control Apparatus, of which the following, when taken in connection with the drawings accompanying and forming a part hereof, is a full and complete specification.

This invention relates to block signal railway systems wherein clear, caution, and danger signals are exhibited in the cabsior motors equipped with apparatus co-acting' and cooperating with track and track side installations, said signals corresponding with and indicating theconditionof said track and track side, installations.

Among the objects of the invention are to obtain new and novel means to exhibit, in a moving cab or motor traveling on a railway track which is equipped with a block signal-system, the conditions of the track and track side installations in a plurality of blocks in advance of said moving cab or motor, said conditions being responsive to the conditions, whether occupied or unoccupied, of the track rails in said blocks; to

obtain a cab or motor carried apparatus -responsive to the conditions, whether normal or abnormal, and whetherautomatically or manually created, of track or track side installations of blocks in advance of said 1noving cab or motor. Additional objects are to obtain a cab or motor carried apparatus, of

the kind recited, which consists of few parts, not liable to become broken, or to get out of order, which will operate with certainty and accurately exhibit the existing conditions of the track and track side installations, which is understandable by men skilled in the art of railroading, which is economically made and durable, and which will exhibit the Figure 1 is a side elevation of a track a ramp rail, and a diagram of trucks on'said rail and an apparatus embodying thecab or motor carried apparatus mounted on the truck.

Fig. 2 is a diagram of track rails, a ramp rail, cabs or motors on said rails, and track and track side installations controlled by track conditions, (whether occupied or unoccupied).

Fig. 3 is a top plan view ofan apparatus embodying the cab or motor carried con.- struction embodying the invention, the upper portion, of the shell or case being re moved to expose the operable parts to view.

Fig. 4 is a vertical section online ll of Fig. 3, viewed as indicated by arrows, with the'parts which are in elei'ration in the same position as insaid Fig. 3. Fig. 5 is an elevation of the operable parts of said apparatus, and of a portion of a ramp rail, a part of the case of the apparatus being removed and a part in cross section.

Fig. 6 is an end elevation, on line 6-6 of Fig. 5, viewed as indicated by arrows andin similar position as in said Fig.- 5. L

Fig. 7 is an elevation of the operable parts which are illustrated in Fig. 5, in a different position from that illustrated in; said Fig. 5; Fig. 8 is an end elevation, on line 8-8 of Fig. 7 viewed as indicatedby arrows and in similar position as in said Fig. 7.

Fig. 9 is an elevation of the operable parts which are illustrated in Figs. 5 to 8, inclusive, said parts being in an additional different position, and p Fig. 10 is an end elevation, on line 10-.1O of Fig. 9, and in similar position as in said Fig. N

Fig, 1 is a diagrammatic view showing the relative position of the permanent magnet and electro-magnet. V

A reference character applied to designate a given part indicates said, part throughout the several figures of the drawing, wherever the same appears.

Referring to Figs. 1 and the numerals 1, 2, 3 and 4 represent insulated blocks of a railway system, and in Fig. 2 the several parts and members illustrated are shown in diagram. X, X (Fig. 2), represent motors or cabs positioned in blocks 1 and 4, respectively, motor X being assumed to be the moving one, and to be traveling in the directon toward motor X Of the track and track side installations which are indicated are controlled by motor X in block 4, and

are indicated in the positions automaticallycreated thereby. The several elements and members which are indicated in Fig. 2, and about to be described, are respectively provided with an index numeral which indicates the block in which they are installed, for instance, A represents one rail of the track in block 1, A the same rail in block 2, A said rail in block 3, and A said rail in block 4. B B B and B, respectively represent the other rail of the track, in blocks 1, 2, 3 and 4. C C and represent track relays in blocks 2, 3 and 4. D 65 D (P, and D 0Z represent electrical con ductors which are respectively attached, at one end, to the relays C C and" C and at the other end to rails A A A and B B and B E E E and E, represent batteries, in blocks 1, 2, 3 and 4, respectively, and 0, 0 represent electrical conductors, which are attached to said batteries and to rails A and B, in the blocks in whichsaid batteries are positioned. F F and F represent track side relays which are positioned in blocks 2, 3 and 4, respectively. G G G represent track side batteries, in blocks 1, 2, 3, and 4, respectively. H H H and H represent electric conductors which are respectively attached to one ters minal of a relay of the F series and to a battery of the G series in the block indicated by the index numeral applied thereto. The track side relay in block 1, and the track side battery of block 4 are not illustrated, but the location and conductor connections thereto are similar to those in blocks 2 and 3, that is, conduct0r'H from battery G is attached to the relay of the F series in block 1, and the conductor H in block 4 is attached to a battery of the G series, in said block 4. The positive poles of the batteries of the G series which are indicated by the characters G G and G are indicated by a plus sign, and the negative poles of said batteries are indicated by a minus sign.

h 72 and [L3, represent electric conductors which, at one of the ends thereof, respectively, are attached to the coils of relays F F and F and at the other ends are branched into the conductors of the I series of the next block in advance. That is, ]t is branched into conductor 1 72. into conductor I and it into conductor 1*.

J j J j J and 7', represent movable conductors which are controlled by relays C C and 0*, respectively, and K K 70 K 73 respectively represent contact points co-actuable with the several movable conductors of the J and 7' series in the several blocks illustrated.

L L and L respectively represent conductors which connect the positive poles of the batteries of the G series'with the movable conductors of the J series in the several blocks 2, 3 and 4, and Z Z and Z represent conductors which are attached to the movable conductors of the j series and are branched into the conductors of the H series in blocks 2, 3 and 4; it being observed that conductor Z is branched into conductor H conductor Z" is branched into conductor H and conductor Z is branched into conductor M m M m and M on represent movable conductors which are controlled by relays F F and F, respectively.

N P N P N P, represent contact points which are co-actuable with movable conductors M M and M, respectively, and a 9 a 12 and n [9, represent contact points which are co-actuable with the movable conductors m m and m, respectively.

0 represents a conductor which is attached to the descending side 3 of the ramp in block 1, and extends to contact points N 72 in block 2, being branched to extend to both said points. 0 represents a conductor from descending sideg of the rampin block 2 to contact points N 79 in block 3, said conductor being branched in the same manner as conductor 0 0 represents a conductor from descending side of the ramp in block 3 to. contact points 1 39 in block 4.

Q represents a conductor from contact points P and a in block 2, (being branched as are the conductors of the 0 series as last above recited) to railB' in block 1. Q and Q} represent conductors similar to conductor Q which extend from contact points P 91 and P of, to rails 13 and B of blocks 2 and 3.

Z represents insulation between the as cending sections Y Y and Y of the ramps in blocks 1,2 and 3, and the descending sections y 3 of said ramps, and between the rails A A A A and B B B and B The several ramps are insulated in the usual manner. 7

Cab X on the rails in block 4' shunts relay G the main portion or part of the current generated by the battery E, flowing from said battery on one rail of the track to motor or cab X through the wheels and axles of the cab to the other rail of the track and on said other rail to the battery. Relay C not receiving sufficient current to energize it sufiiciently to hold movable conductors J j to contact points K 70*, the track side installations of which said movable members are elements, will not be continuous. The track side installation starting from the positive pole of battery G and extending over conductors and contact points L J K, 1*, M-", N and O to the descending section 3 of the ramp (in. block 3), is not continuous, because of being broken between movable conductor J 4 and contact point K, and said descending section will not be energized when the shoe of the cab .or motor carried apparatus is in contact therewith.v

At the same time the relay F in block 3, is deener ized by the breaking of the con.- tinuity of contact between movable conductor J and contact point K, the conductor h being branched into conductor 1, and extending from thence to relay F and by said conductor H to the negative pole of battery or generator G The relay F being deenergized the movable conductors M 772?, will break contact with contact points N 11 and make contact with contact points P 10 A continuous track side installation. from battery G will thereby be obtained, which starting from the positive pole of battery G com-- prises conductor L movable conductor J contact point K conductor 1 movable conductor M contact point P conductor Q to rail B and from descending section of said block 2, conductor 0 contact point 39 movable conductor m conductor i contact point movable conductor j conductor Z and conductor H (conductor Z being branched into conductor H to the negative pole of said battery G The track installation of'block 2 is not affected by the motor or cab X on the rails in block 4, and hence, the relay C is energized sufficiently to hold movable conductor J 2 in contact with contact point K and from battery G there is a continuous track side installation from the positive poleof said battery to the descending section'y of the ramp, (in section 1'), which includes L J K I M N and O and from rail B to the negative pole of said battery which includes Q 11?, m i 13 Z and in, (Z being branched into H It occurs, therefore, when the shoe of the motor or cab carried apparatus is brought into contact with the descending side or section to co-act with the track side installa tion which controls said descending section, said section will be positively energized. When said shoe comes in contact with the descending section 11/ said section will be negatively energized; And when said shoe comes in contact with the descending section it will not be energized.

In Figs. 3 to 10, inclusive, W represents the shell or case of the cab or motor carried apparatus about to be described.

R represents a lever which is fulcrumed at one end thereof on shaft'r, and is pro vided at the other end with head R T represents a slot in lever B, midway of the ends, and S represents an abutment in said slot, said abutment being Iigidlysecured to plunger S so that movement of said plunger produces corresponding movement of head R and said lever is turned on its fulcrum:

and the suspension of said lever in a deter mined position correspondingly suspends said plunger. Head R is provided with recesses, R 1' which are illustrated as on ops posite sides thereof, and R r represent pawls which are adapted to, engage with said recesses, respectively, and when in engagement therewith to hold said lever in said determined positions, thereby suspending said plunger correspondingly. Pawls R it, and tying said pawls loosely together..

R represents an electromagnet, and 7 the pole piece thereof. R represents a permanent magnet which forms the armature of electromagnet R Magnet R is secured on frame R, as by screws 1' ,1" and is pivotally mounted on pin R fulcrum on which frame R and magnet R swings, said fulcrum being stationary, andillustrated in Fig. 3 as being mounted on ringr which extends around the coil of electromagnet R".

R 1' represent the poles of magnet R which are indicated by plus and minus signs .in Fig. 11, and the pole piece 1" of eletromagnet R is extended to between said poles. Y

- When the electromagnet. R is energize by current flowing through its coils, in one direction, the pole piece 1 is excited and magnet R which is of opposite polarity,

and repel the one. of like polarity. This the position illustrated in Fig. 10. At the same time, bar It will be forced, relative to said pawls, into the position illustrated in Fig. 6, on the upward movement of head R to its highest possible position by said head being forced between said pawls and forcing them into the position illustrate'din Fig. ,6,thereby returningthe bar R and frame R to neutral position. Said pawls remaining in said neutral position, on the descent of the shoe T of the apparatus, the plunger S will descend therewith, and head R 'be moved to the position indicated by broken Pin R forms the lines in Fig. 6. In case the descending section of the ramp is not energized when shoe T comes in contact therewith the permanent magnet and frame R do not move from said neutral position, and the head R descends between the pawls R 1' on the clescent of shoe T, the lever R turning on its fulcrum.

Plunger S is vertically movable in cylindrical chamber S (formed by walls S S, S represent stufling boxes or glands. S represents a head which is rigidly secured in cylindrical walls S. Gland S is represented as secured in head S S represents an air retaining cup, or piston ring, and S a nut on plunger S holding said cup or ring in place on plunger S. S represents an annular groove on plunger S which, when said plunger is in the position in which it is illustrated in Fig. 5, forms a by-pass around the plunger between passage way U and passage way u. U represents a passage way communicating at its inlet end with the train pipe of an air brake system and at its outlet end with the chamber S and a, a represent outlets from said chamber. Outlets a, a may discharge to waste, to signals or to other devices, as desired, the utilization of the flow of air from said discharge not being included in this invention. Plunger S being in the position in which it is illustrated in Fig. 9, the flow of air therethrough is suificient to make a light application of the brakes of the air brake system; and when said plunger is in the position illustrated in Fig. 4:, the flow of air from inlet U, through the by-pass S and outlet is suflicient to make a heavy application of said brakes. The plunger is in the position indicating caution when said light application of the brakes is effected; and in danger when said heavy application is made. When head R is in position indicating 'clear, see Fig. 7, train pipe air pressure prevails in chamber S plunger S is not in position however to permit a flow of air therethrough from inlet U to outlets a, M or either of them, and no application of the brakes is automatically effected. The plunger S is, therefore, moved by the air under pressure in said chamber S in an advance direction, when not arrested by one or the other of the pawls R W, to danger position.

The shoe T is connected to links T T by pivots t, t. 6 represent slots in links T T and T T represent pins in said slots. Pins T T are secured in abutment-s t 25 said abutments being integral with or rigidly secured to case W.

Case W is insulated from the truck, motor or cab in which it is installed, as my insulating material Z (Fig. l), in the ordinary way, and W ,Fig. 3, represents a conductor connecting case W to the coil of electromagnet R and W a conductor from said coil to the frame of the truck on which the ap paratus is mounted. 1

lVhen shoe T is in contact with the descending section of a ramp and the wheels of the motor or cab in which the apparatus is mounted are on a rail of the B series a closed electric circuit is formed, (the track side installations being continuous), the ele ments of said circuit which are in said apparatus comprisingshoe T, links T T frame WV, conductor V the coil of electromagnet It", conductor and the truck frame and wheels.

The plunger S, whether suspended or not by lever B as hereinbefore described, is in position to be engaged by shoeT, and as said shoe is brought into contact with the ascending section of a ramp it is raised, and upon said raising it engages and raises the plunger. As said shoe moves on to the descending section the non-suspension or sus pension of the plunger by lever R, is determined by the non-energized or energized condition of said section, and the direction of the flow of current energizing it, said direction depending on the clear and cantion condition ofthe track side installation, as hereinbefore described.

ElectromagnetuR being energized by a current flowing through the coil thereof in one. direction," the armature R will be drawn or pulled in one direction by the pole piece 1*, and upon said current flowing through said coil in the opposite direction said armature .will be drawn or pulled in the opposite direction from its neutral po sition. Y V

In case said descending section is energized as hereinbefore recited relative to section f, the electromagnet R will be energizedto move its armature from the neutral position illustrated in Fig. 6 to the position illustrated in Fig. 8; pawl R will engage with recess R and clear will be indicated; The circuit'on which said current is assumed to flow comprises, from the positive pole of battery G conductor L movable conductor J contact point K con ductor I movable conductor M contact point N conductor 0 descending section f of the track side installation, shoe T, links T T shell W, conductor the coil of electromagnet R conductor 1V and the frame of motor or truck X, of' the cab carried apparatus, and rail B of the track, and conductor Q contact point 91?, movable conductor m conductor 2' contact point 72 movable conductor 7' conductor Z conductor H to the negative pole of said bat tery G i It being observed that conductor Z is illustrated and described as branched into conductor Hi, and that the descending section 3 is positively energized, ashereinbefore recited. V

The above recited pull or draw of the armature R will continue as head R descends with the descent of plunger S, until the corresponding recess (R is in position to permit said armature to move and move bar R and pawls R r whereupon said armature will respond to said draw or pull and move frame R", bar R and said pawls,

moving cess R Assuming the motor, cab or truck X to have traveled into block 2 and said descending section y is ener ized as hereinbefore recited, the armature it will be drawn or pulled by the energizing of the electromagnet R from the neutral position illustrated in Fig. 6 toward the position illustrated in Fig. 10, and said draw or pull will continue as head R descends with the descent of plunger S, until the corresponding recess, (W), is in position to permit said armature to move, (moving bar R and pawls R 1 whereupon said pawl T will enter said recess. Said lever B will at this time be in position indicating caution, and thecircuit which is closed and energized comprises, the positive pole of battery G ,in block 2, and the following elements, L J K I M P Q of the track side installation, to rail B the wheels and frame of truck X, conductor W the coils of electromagnet R conductor case or shell W, links 'T T and shoe T, of the cab carried members, (as before, but the current flowing in the opposite direction), and again of the track side installation of blocks 2, and 3, members y 0 22 m 2' 70 f, Z and H and the negative pole of said .battery Gr".

Assuming the motor, cab or truck X to have traveled into block 3, upon said shoe T coming into contact with descending section y (it being non energized) said electromagnet R will not be energized, and its armature will not be moved from the posiawl R into en a ement with retion thereof illustrated in Fig. 6, and said head R will descend from the position thereof there illustrated by full lines to the position indicated by broken lines, permitting plunger S to descend with the descent of shoe T, and danger will be indicated by said head R I The cab carried elements are identical in the last above recited conditions and the failure of the electromagnet R from being energized is due to the fact that the continuity of the track side installation is broken, the break occurring because movable conductors J j are not in cont-act with contact points K*. 76 as herein before recited.

From the foregoing description and illustrations of the manner in which, upon the contact of the cab carried shoe with the descending section of a ramp rail the electromagnet R is energized by a flow of electrical energy therethrough in opposite directions, or whereby its energizing is not effected,

depending on the conditions of the track side installations; and the description and illustration of the manner in which the shoe of the cab carried apparatus is raised from its lowest to its highest position upon the contact of said shoe with the ascending section of said ramp; and the further explanation, that in whatever position the plunger may be by reason of'its suspension or nonsuspension by the latching mechanism of the apparatus, said shoe, in its upward travel will move said plunger upward and destroy the condition created by the contact of said shoe with the last ramp contacted with and mechanically force said latching mechanism into a neutral position, in readiness to be reset by the co-action of the track side installation and the cab carried apparatus, as said shoe moves down the descending section of the ramp, the operation of the apparatus and the track side installations is believed to have been fully explained.

In the ramp illustrated and described the words ascending and descending imply, merely, that trains are moving in a direction to make such words applicable thereto; and if it be assumed that trains are moving in' the opposite direction said words are applicable to the opposite sections, as shown; and in illustrating and describing the train as moving in one direction, I do not thereby limit myself to a track side installation and co-acting motor or cab carried apparatus which is connected to one section only of the several ramps the limitation of the connection of conductors of the track side installation to one section of a two section ramp being simply for the sake of brevity and clearness in the illustrations and description of the embodiment of the invention and its operation.

The chamber S being, except for a brief apex of the ramp, in'communication with the air brake system of the train by means of passage way and chamber inlet U, the pressure in said chamber corresponds with the pressure of the train pipe of said system. It'is the lessening of the pressure in said chamber and a corresponding lessening of the pressure in the train pipe which causes this apparatus to control the application of brakes in said system. Further, said air pressure in said chamber S tends to advance plunger S, and when lever R and said plunger are suspended by one of the pawls R T in engagement with a corresponding recess, said air pressure tending to advance plunger S, thereby force-s head R down onto said pawl, thus preventingthe jarring of said pawl out of engagement with said recess.

I claim:

1. In a block train control system, a track side installation in each of the blocks of said system comprising a two-part ramp consisting of an insulated ascending and an insulated descending section and a-conductor connected to said descending section, said track side installations arranged to control the electrical condition of said descending section to correspond with the conditions, whether occupied or unoccupied of a determined number of blocks of said system, in combination with a cab carried apparatus comprising a shoe, arranged to coact with said ramp, a plunger mechanically movable in a determined direction by the movement of said shoe in said direction, electro-responsive means to suspend said plunger in a position corresponding with and indicating the electrical condition of said descending section.

2. Ina block train control system, a track side installation in each of the blocks of said system comprising a two part ramp consisting of an insulated ascending and an in sulated descending section, and a conductor conn cted to said descending section, said track side installation arranged to control the electrical condition of said descending section to correspond with the condition, whether occupied or unoccupied, of deter mined number of blocks of said system, in combination with a cab carried apparatus comprising a shoe arranged to co-act with said ramp, a plunger mechanically movable in a determined direction by the movement ot' said shoe, electroresponsive means to suspend said plunger in a position corresponding withand indicating the electrical condition of said descending section, said plunger arranged, on said mechanical movement thereof to release the means whereby existing suspending means are maintained.

3. In a cab carried apparatus cooperable with a track side installation which is provided with a two part ramp, having an ascending and a descending section, and means to control the electrical condition of said descending section, the combination of a movable shoe, a plunger and a lever connected to said plunger, electroresponsive means to arrest and maintain said lever in a determined position, and mechanically operable means to release said arresting means, said shoe related to said ramp so as to be mechanically operated by the ascending section thereof and to be electrically responsive to the descending section, and means to convey the electric condition of said shoe to said means to arrest.

4. In a block train control system, a track side installation in each of the blocks of said system comprising a two part ramp having an ascending and a descending section, a conductor. connected to said descending section, said track side installation arranged to control the electrical condition of said descending section to correspond to the condicab and said chamber, an outlet from said chamber, a movable plunger in said chamber, adapted to be yieldingly forced in one direction, means responsive to the electrical condition of said descending section adapted to arrest the movement of said plunger in said direction'in a selectively determined position, said plunger arranged to cut off communication between said chamber and said outlet when in one of said selectively determined positions, and to establish restricted communication between said chamher and said outlet when arrested in the remaining one of said selectively determined positions. I V

5. In a block train control system, a track side installation in eachof the blocks of said system comprising a two part ramp having an ascending and a descending section, a conductor connected to said descending section, said track side installation arranged to control the electrical condition of said descending section to correspond with the condition, whether normal or abnormal, of a determined number of blocks of said system in advance of said descending sec tion, in combination with a cab carried apparatus comprising a shoe, arranged to coact with said ramp, a plunger mechanically movable in a retracted direction by said shoe and yieldingly movable in an advance direction, electroresponsive means controlled by the electrical condition of said descending section to selectively position said plunger.

1 6. In a bl ock train controlsystem, a track side installation in each of the blocks of said system comprisinga two part ramp having an ascending and a descending section, in combination with a cab carried apparatus comprising a shell provided with a chamber, a communicating passageway between the air brake system of the cab and an outlet from said chamber, a shoe arranged to co-act with said ramp, a plunger movable in said chamber and arranged to be yieldingly forced in an advance direction, means responsive to the energized electrical condition of said descending section to selectively arrest said plunger, and, said descending section not being energized, said yieldingly forcing means arranged to sufficiently advance said plunger to establish communication with said outlet' from said chamber.

7. In a traincontrol system, a cab carried apparatus provided with a chamber, a com municating passage way between the air brake system of the cab and said chamber,

and an outlet from said chamber, a plunger in said chamber said plunger adapted to be moved in one direction by the air in said chamber, means responsive to the flow of an electric current in opposite directions to selectively arrest said movement of said iluiwer said lun 'er arran ed to close said h 7 b b outlet when arrested in one position and to establish restricted communication through said outlet when arrested in another position.

8. In a train control system, a cab carried apparatus having as an element thereof a movable plunger and means to apply air under pressure to said plunger to yieldingly force said plunger to an advanced p0. sition, a plurality of latch members adapted to respectively limit the advance movement of said plunger, in combination with atrack side installation arranged to mechanically retract sai'd plunger, and means to selectively move said latch members into position to limit said advance movement of said plunger.

9. In a block train control system, a track side installation in each of the blocks of said system comprising a two part ramp having an ascending and a descending section, in combination with a cab carried apparatus provided with a chamber and comprising a shoe arranged to co-act with said ramp, a plunger movable in said chamber, yielding means to move said plunger, means adapted to selectively arrest said movement of said plunger, said ascending section, said shoe and said plunger co-acting to release and move said arresting means to inoperative position.

10. In a cab carried apparatus cooperable with a track side ramp provided with an ascending and a descending section, a movable shoe arranged to co-act with said ascending section and electrically responsive to said descending section, a movable plunger operable to a retracted position by said shoe and to an advanced position by air under pressure, a lever, means to join said lever and plunger so that movement of said plunger moves said lever and the suspension of said lever suspends said plunger, a plurality of means to arrest movement of said lever during the advance movement of said plunger, and means to selectively actuate said means to arrest.

11. A cab carried mechanism comprising a member adapted to be advanced by air under pressure, a lever connected to said member and provided with a plurality of engageable elements, means adapted to be advanced into position engageable with said elements, in combination with an electroresponsive member arranged to selectively advance said last means into said engageable position.

12. A cab carried mechanism comprising a member adapted to be advanced by air under pressure, a lever connected to said member and provided with a plurality of engageable elements, a plurality of members adapted to be advanced into engageable position with a corresponding one of said elements, in combination with an electroresponsive member arranged to selectively advance said last members into said engageable position.

13. A cab carried mechanism comprising a member adapted to be advanced by air under pressure, a lever connected tosaid member and provided with a plurality of en gageable elements, a plurality of members adapted to be advanced into position engageable with a corresponding element, in combination with an electroresponsive mem ber arranged to selectively advance said last members into engageable position, and mechanically actuable means to retract said plurality of members.

14. In a train control system, a track side installation comprising as elements thereof a source of electrical energy, a member electrically responsive to normal and abnormal conditions of a plurality of adjacent blocks of said system, means to transmit electrical energy from said source to a cab carried member responsive to the direction of flow of said electrical energy, a plurality of latch members, said cab carried responsive member arranged to selectively move said latch members to operable position.

15. In a train control system, a track side installation comprising as elements thereof a source of electrical energy, a member electrically responsive to normal and abnormal conditions of a plurality of adjacent blocks of said system, means to transmit electrical energy from said source to a cab carried member responsive to the direction of flow of said electrical energy, a plurality of latch members, said cab carried responsive member arranged to selectively move said latch members to operable position, and meehanically operable means to move said latch members to I inoperable position.

16. A cab carried mechanism comprising as elements thereof a member adapted to be yieldingly forced to an advanced position by air under pressure, and a plurality of electroresponsive members adapted to selectively arrest advance movement of said first member, in combination with a track side i11- stallation comprising a member adapted to mechanically move said arresting members to an inoperative position and to be selectively energized to move said electroresponsive members to operative position.

' ANDREIV J. BROOKINS.

lVitnesses o CHARLES TURNER BROWN, B. S. BROWN. 

